Download Beet and Swiss Chard Production in California B

PUBLICATION 8096
Beet and Swiss Chard
Production in California
WAYNE L. SCHRADER, University of California Cooperative Extension Farm Advisor, San
Diego County, and KEITH S. MAYBERRY, University of California Cooperative Extension
Farm Advisor, Imperial County
UNIVERSITY OF
CALIFORNIA
Division of Agriculture
and Natural Resources
http://anrcatalog.ucdavis.edu
INTRODUCTION
Beets (Beta vulgaris var. crassa) and Swiss chard (B. vulgaris var. cicla) are members
of the Chenopodiaceae (goosefoot family). In addition to beets and Swiss chard, this
family includes mangel-wurzel (B. vulgaris var. macrohiza), sugarbeets, and the weed
lambsquarter (Chenopodium album). This publication covers table and fresh-market
beets, processing beets, and Swiss chard (beets grown for their edible leaves). It does
not cover mangel-wurzel (beets used as a livestock feed) or sugarbeets (beets grown
for commercial sugar production).
Beets are thought to have been developed from the seabeet (Beta maritima),
which is native to southern Europe. They have been cultivated since at least the third
century A.D. and were fully developed as agronomic crops in the nineteenth century
by German and French breeders.
Beets are used for bunched greens, bunched roots, beet roots, and by processors
for several different products. The immature leaves of Swiss chard are harvested for
braizing and salad mix; the mature leaves are harvested for bunching.
T Y P E S A N D C U LT I VA R S
Processing Beets
Beets grown for processing are usually cylindrical in shape. Cylindrical beets offer
greater uniformity and efficiency for sliced beet production, a major requirement for
processors. Nonhybrids: Detroit Short Top, Ruby Ball, and Scarlet Supreme. Hybrid:
Red Ace F1 (Cercospora-tolerant). Hybrid beets have the advantage of greater
seedling vigor and improved top growth and resistance to certain diseases such as
Cercospora. On the negative side, the vigor of hybrid beets may result in beet roots
going “out of grade” (see “Harvesting and Handling,” below) more quickly if harvest
is delayed by poor weather or other reasons.
Table Beets
Table beets are also known as fresh-market beets. Red, round types: Detroit Stains,
Ruby Queen (bulbs well when crowded). Hybrids: Red Ace F1, Hybrid Pacemaker III.
For trial: Avenger F1, Big Red, Ivax (monogerm), Warrior F1. Bunching: Crosby’s
Greentop, Winter Keeper (long-season, for late-fall gardening use).
Novelty Beets
Some beets have unusual colors or shapes; these are known as novelty beets. Red
elongated: Cylindra, Forono (half-long). Alternating red and white: Chiaggia. Yellow,
round: Burpee Golden. Yellow elongated: Burpee Golden. White, round: Showhite,
Albino. Most cylindrical varieties produce beets with an “earthy” taste, which has
limited their adoption.
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ANR Publication 8096
Spinach Beets
Spinach beets (Beta vulgaris orientalis group) are table beets grown for their succulent
leaves, which can be harvested over an extended period. The main variety is Burpee
Red Ball.
Swiss Chard
Swiss chard is a beet grown for its edible leaves. It has large, well-developed petioles
that may be green, red, or multicolored. Green petiole: Lucullus. Red petiole:
Charlotte, Rhubarb Chard. Multicolored petiole: Bright Lights (red, yellow, white,
orange, purple, pink).
C R O P E S TA B L I S H M E N T
Beets are grown as annuals. They are a cool-season crop that grows best when air temperatures are between 50ºF and 64ºF (10ºC and 17.8ºC). Higher temperatures lead to
rapid growth and white rings in the interior of the beet root (zoning). The minimum
soil temperature for beet seed germination is 41ºF (5ºC). Optimal temperatures for
beet germination are 50º to 86ºF (10º to 30ºC). The maximum temperature for germination is 95ºF (35ºC). Beets require a cold period of 2 weeks at 39º to 50ºF (3.9º to
10ºC) to induce flowering. Beets will tolerate frosts and mild freezes.
Seeding or Planting. In the field, first plantings are usually made in March or
April. Beets grown for processing can be planted from early May to late June. Sow
seed every 2 or 3 weeks to provide a continuous supply of bunched beet roots. For
fresh market beets, plants should be 2 to 3 inches (5 to 7.5 cm) apart. Rows are normally 32 to 40 inches apart (81 to 102 cm), and plants are usually spaced 12 to 24
inches (30.5 to 61 cm) apart. Plant seed from 0.4 to 1 inch (1 to 2.5 cm) deep. It normally takes 8 to 10 pounds of seed to plant one acre (9.0 to 11.2 kg/ha). Table beet
seed numbers approximately 1,600 per ounce (1,700 per 30 g). Swiss chard is usually
planted on 40-inch (102-cm) beds with a spacing of 9 to 12 inches (23 to 30.5 cm)
between plants. It takes about 6 to 8 pounds of seed to plant one acre (6.7 to 9.0
kg/ha).
Small (baby) beets intended for whole pack and pickled packs may be produced
by reducing the spacing between rows to about 10 to 15 inches (25 to 38 cm) and
maintaining about 30 to 35 plants per foot (100 to 115 per meter) of row. More commonly, baby beets are sorted out of the regularly harvested product in normal processing operations.
SOILS
Beets prefer deep, friable, well-drained soils such as sandy loam, silt loam, or muck.
They may be grown on heavier (more clayey) soils, but harvesting is more difficult
and root growth may be impaired. High levels of organic matter in the soil are desirable and will help ensure an adequate moisture supply. The beet has a large root system that extends down in the soil about 3 feet (1 m) or more unless root growth is
restricted.
Uniform soil moisture is essential for best quality. Rotate crops to avoid damping-off and root rot diseases. Beets are sensitive to damping-off on soils that may flood
or have poor aeration. Adjust soil pH to 6.0 or higher for maximum yields. Follow
soil test recommendations for liming rates. Fields in which processing beets are to be
planted are usually tested by the processor for residues of chlorinated hydrocarbons
and rejected if these residues are found to be unacceptable.
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ANR Publication 8096
FERTILIZERS
Preplant soil tests are the most accurate guides to fertilizer requirements. Good management practices are essential if optimal fertilizer responses are to be realized in
beets. These practices include use of recommended varieties, selection of appropriate
soils, good weed control, disease and insect control, good seed bed preparation, proper seeding methods, and timely harvest.
Because of the influence of soil type, climatic conditions, and other cultural
practices, crop response from fertilizer may not always be accurately predicted. Soil
test results, field experience, and knowledge of specific crop requirements help determine the nutrients needed and the rate of application.
Recommended soil sampling procedures should be followed in order to estimate
fertilizer needs. The University of California Cooperative Extension (UCCE) advisor
in your county can provide you with soil sampling instructions and information
sheets. UCCE offices do not perform laboratory tests.
Nitrogen
Application of l50 to 200 pounds per acre (168 to 224 kg/ha) of elemental nitrogen
(N) is recommended. The lower rates of nitrogen should be used following a good
legume crop such as alfalfa or red clover. The higher nitrogen rates should be used
following grain or grass seed. Broadcast the nitrogen before planting or apply up to
one-half of the nitrogen as an early-season top dressing. Nitrogen is important in
maintaining the top growth needed for efficient harvest, since traditional harvesting
equipment handles beets by their tops.
Phosphorous
Phosphorus (P) is necessary for vigorous early seedling growth that may reduce damage from damping-off. Band 50 to 70 pounds per acre (56 to 78 kg/ha) of phosphate
(P2O5) as superphosphate or triple superphosphate fertilizer l inch (2.5 cm) directly
beneath the seed. Warning: Severe seedling burn can result if nitrogen-phosphorus
mixtures or fertilizers containing potassium or boron are banded directly beneath the
seed. Broadcast and work the remainder of the phosphorus into the seedbed before seeding as indicated
Table 1. Phosphorus application rates for beets
in table 1.
Apply this amount of phosphate (P2O5)
If the soil test for P reads (ppm)
0–25
lb/acre
kg/ha
120–150
134.4–168
25–50
70–120
78.4–134.4
>50
50–70
56–78.4
Potassium
Broadcast potassium in the form of potash (K2O) and
work it into the soil before planting. Use the rates
indicated in table 2.
Sulfur
Table 2. Potassium application rates for beets
Apply this amount of potash (K2O)
If the soil test for K reads (ppm)
0–75
lb/acre
kg/ha
120–150
134.4–168
75–150
80–120
89.6–134.4
150–225
60–80
67.2–89.6
>225
none
none
Plants absorb sulfur (S) in the form of sulfate (SO4).
Fertilizer materials supply sulfur in the form of sulfate and elemental sulfur. Elemental sulfur must be
converted to sulfate in the soil before the sulfur
becomes available to plants. The conversion of elemental sulfur to sulfate is usually rapid for finely
ground (less than 40 mesh) material in warm, moist
soil. The sulfur requirements of table beets can be
provided by one of the following:
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ANR Publication 8096
• applying 15 to 20 pounds per acre (16.8 to 22.4 kg/ha) of sulfur in the form
of sulfate at planting time; or
• applying 30 to 40 pounds per acre (33.6 to 44.8 kg/ha) of sulfur as finely
ground elemental sulfur the preceding year; or
• applying more coarsely ground elemental sulfur at higher rates and less frequently.
Magnesium
Applications of 10 to 15 pounds per acre (11.2 to 16.8 kg/ha) of magnesium (Mg) are
suggested when the soil test value for magnesium is below l.0 meq Mg/100g of soil.
Magnesium can also be supplied in dolomite, a liming material that reduces soil acidity with about the same degree of effectiveness as ground limestone (see “Lime,”
below). If used, dolomite should be mixed into the seedbed several weeks before
seeding.
Boron
Boron deficiency (canker) in table beets has been severe in some areas of California.
In these areas, foliar applications of water-soluble boron (B) materials are needed in
addition to soil application. Lack of moisture aggravates boron deficiency. Boron
should not be banded; instead, it should be applied evenly to the field. If all required
boron is applied as a single preplant broadcast treatment, 8 to 10 pounds per acre
(9.0 to 11.2 kg/ha) of elemental boron is usually used. However, rather than this single application, it is recommended that boron be applied in one of the following programs:
• Preplant treatment: Apply 3 to 5 pounds per acre (3.4 to 5.6 kg/ha) of boron
(broadcast and disked in). This rate has been adequate where canker has not
been severe.
• Combination treatment: This is to be used where canker is severe or where
beets are held for late harvest. Make a preplant application of 3 to 5 pounds
per acre (3.4 to 5.6 kg/ha) of boron (broadcast and disked in) plus two to
three foliar applications of water-soluble boron materials. For foliar applications, use l pound per acre (1.1 kg/ha) of boron in 50 to 100 gallons (189 to
378.5 l) of water. Apply at the time of enlargement (bulbing) of beet roots and
when beet roots are 1.5 to 2 inches (4 to 5 cm) in diameter. Make an additional application 10 to 14 days later.
Lime
Table 3. Lime applications for beets
Apply this amount of lime
If the buffer test for lime reads
<5.2
ton/acre
metric ton/ha
4–5
9.0–11.2
5.2–5.7
3–4
6.7–9.0
5.7–6.0
2–3
4.5–6.7
6.0–6.3
1–2
2.2–4.5
>6.3
none
none
Table 4. Beet water use
Total seasonal evapotranspiration
15.1 in (38.4 cm)
Peak evapotranspiration rate
0.21 in/day (0.53 cm/day)
Maximum allowable water depletion
50%
Critical moisture deficit period
seed germination, root expansion
Table beets are less tolerant of soil acidity than bush
beans or sweet corn. Lime applications should be
made when the soil pH is 5.8 or below, or when calcium levels are below 7 meq Ca/l00g of soil (see table
3). The liming rate given in table 3 is based on 100score lime. Lime should be mixed into the soil at least
several weeks before planting, preferably during the
previous fall. A lime application is effective for several
years.
I R R I G AT I O N
Irrigate beets carefully, especially early in the season
so as to avoid overwatering (see table 4). Waterlogging can cause beet leaves to turn red and cause
plants to stop growing for a time. A total of 12 to 14
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ANR Publication 8096
inches (30.5 to 35.5 cm) of water may be needed in California production areas. Soil
type does not affect the amount of total water needed but does affect frequency of
water application: lighter soils need more frequent water applications with less water
applied per application. Excessive irrigation or moisture early in the growing season
can encourage damping-off and other seedling disorders. A lack of water, however,
can aggravate boron deficiency.
Moisture management in beets is especially important during stand establishment, the early growth stage, and root expansion. Since small beet seed are unable to
emerge when surface crusting occurs, irrigation during the preemergence period
should strive to maintain a loose soil surface. This often requires frequent, light irrigations. Conversely, deep, excessive irrigation, which causes anaerobic soil conditions,
can encourage damping-off of emerging seedlings and temporary cessation of growth
in young plants. In the remainder of the growing season, available soil moisture
should not be depleted by more than 50 percent. Because beet roots develop most of
their size in the last half of their growth period, irrigation is especially critical during
this time. Water deficit during this period will have the greatest negative impact on
yields. A balance must be struck, however, between maintaining adequate moisture
while minimizing wetness in the canopy that promotes diseases caused by Alternaria,
Cercospora, and Ramularia spp. fungi. During the last half of the growing period, irrigate only early in the day to allow for rapid canopy drying whenever possible.
The peak water use for beets, which occurs in July, is approximately 0.21 inches
(0.53 cm) per day. On most soils, weekly irrigation during the peak is adequate. With
sandy and sandy loam soils, however, irrigation may be required as frequently as
every 3 to 4 days.
P E S T M A N AG E M E N T
Refer to the University of California IPM pest management guidelines at
http://www.ipm.ucdavis.edu for more information on insect, disease, and weed control
for beets and Swiss chard.
P H YS I O L O G I C A L D I S O R D E R S
The main physiological disorder of table beet roots is zoning, in which alternating red
and pale bands appear in a root cross-section. The pale areas do not accumulate the
deep red anthocyanin pigment normally associated with red beets, and the rings may
remain nearly colorless or white. This disorder is most pronounced in hot weather
and when table beets are grown in climates to which they are not well adapted. Most
commercial beet production is in Oregon, New York, and Wisconsin, or in more
southerly states during the cooler parts of the year. Contributing factors to zoning are
high temperature and variety. Moderately high temperatures and cool nights favor
good pigment development and decrease the incidence of zoning.
H A RV E S T I N G A N D H A N D L I N G
Timing
Table beets generally reach market size in 42 to 56 days; round beets require 60 to 70
days. Cyllindrical beets for processing require 70 to 80 days, depending on planting
date, sizes desired, and growth season.
Beet roots for processing and fresh market are harvested mainly from July 15 to
the end of October in the cooler areas of California. The prime harvest period is
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ANR Publication 8096
between August 1 and October 1. Individual fields may be harvested over a severalweek period.
Follow processor recommendations for the timing of harvest. Beets are graded
according to their diameter: Grade 1 beets are 1 to 15⁄8 inches; Grade 2 are over 15⁄8 to
25⁄8 inches; and Grade 3 are over 25⁄8 to 31⁄2 or 4 inches, depending on processor
requirements. Beets are usually harvested when their size distribution approaches 25
percent Grade 1, 60 percent Grade 2, and 15 percent Grade 3 paid weight, with about
1 percent culls. These grade distributions vary from year to year according to the type
of product being processed and seasonal variations. In general, the percentage of
Grade 2 changes very little, with most of the yearly or seasonal range differences
occurring in Grade 1 and Grade 3 beets.
Yield
The yield of processing beets averages approximately 18 tons per acre (39.6 T/ha),
with good yields approximately 25 tons per acre (55 T/ha). Fresh market beets are
reported to average 140 hundredweight per acre (15.7 T/ha,) with good yields of 200
hundredweight per acre (22.4 T/ha).
Equipment
Beets are usually harvested and topped with tractor-pulled or self-propelled machines
that are locally custom-built. However, beets can also be harvested with single- or
multiple-row harvesters that are custom built by Krier Engineering of Modesto,
California; contact Mr. Alex Krier at 800-344-3218 for more information.
Because of the slowness and the high maintenance requirements of Scott-Viner
type harvesters, table beet growers in Oregon have begun to use multiple-row diggers
similar to potato harvesters. This requires that the tops be removed before digging.
Top removal is done in two steps: a flail is used to remove leaf blades and as much top
as possible without damage to the roots, followed by a sugar beet–topping device with
three drums of rubber-fingered flails. The latter removes the remaining leaf blades to
within an inch or two of the beet root. Roots are harvested with an AMAC harvester
(see below) that lifts the beets, accomplishes more topping with a hedgehog belt, and
loads the beets into bulk trailers or trucks for transport to the processor. It is important to consider soil type and weed control and to experiment with the proper interval
between toping and digging to allow for the harvest of clean product. Beets are hauled
from the field to the processor in loads of 10 to 14 tons (9.1 to 12.7 T) in double-axle
dump trucks.
Custom-built beet and carrot harvesters are available from:
• AMAC Inc., a Dutch company represented by KPR Inc., POB 608, 375 West
Ave. D, Wendell, ID 83355-0608, phone 208-536-6601, FAX 208-536-6695, Email [email protected], Web site www.KprIncorp.com
• Asa-Lift, a Danish company represented by Miller Farms, Hancock, WI, phone
715-249-5160, FAX 715-249-5860, E-mail [email protected]
• Everett Bros. Engineering Ltd., a British company, USA Tel/FAX 407-396-7515,
E-mail [email protected], Web site www.everett-bros-eng.com
• Univerco Hydraulique (1978) Inc., a Canadian company, 713 Rte. 219,
Napierville, PQ, J0J 1L0, Canada, phone 800-663-8423, FAX 514-245-0068.
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ANR Publication 8096
S TO R AG E
Beet roots should be reasonably dry and free of soil for best storage; they should also
be topped and sorted to remove all those with disease or mechanical injury. Although
processing beets are often stockpiled for several days without serious deterioration,
this practice is not usually recommended. For longer storage, proper storage facilities
are needed. Beets should be stored at 32ºF (0ºC) and relative humidity of 98 to 100
percent. Like other root crops, beets are well adapted to storage. Topped beets stored
at 32ºF (0ºC) can be expected to keep 4 to 6 months under suitable storage conditions. Swiss chard should be stored at 32ºF (0ºC) and 95 to 100 percent relative
humidity. The approximate storage life for chard is 10 to 14 days. Chard should not
be stored with ethylene-producing vegetables.
Either cold storage or cool-cellar storage is suitable for beets, provided the
humidity is kept sufficiently high to prevent shriveling. Cellar storage temperatures
fluctuate and are often higher than 32ºF (0ºC), so the period of successful storage will
be comparatively shorter. The temperature in cellar storage should not exceed 45ºF
(7.2ºC) to minimize sprouting and decay. Because beets wilt readily from loss of
water, they should be kept where the humidity is sufficiently high to prevent excessive evaporation. Small beets soften and shrivel earlier than larger ones.
Beets should not be stored in large bulk. They should be stored in well-ventilated containers, such as ventilated bin boxes or slatted crates, to help dissipate respiratory heat. Increasing the carbon dioxide level in beet storages 5 to 10 percent has
been shown to increase fungal spoilage.
Bunched beets are much more perishable than topped beets, but they can be
stored at 32ºF (0ºC) for 10 to 14 days. Storing them in crushed ice will help keep the
bunched beets cold, especially if refrigeration is not available.
Beet greens and and chard are handled like spinach. Because of their perishability, they should be held as close to 32ºF (0ºC) as possible. At this temperature, they
can be held for 10 to 14 days. Relative humidity of at least 95 percent is desirable to
prevent wilting. Air circulation should be adequate to remove heat of respiration, but
rapid air circulation speeds transpiration and wilting. Satisfactory precooling is
accomplished by vacuum cooling or hydrocooling. These leafy greens are commonly
shipped with package and top ice to maintain freshness. Research has shown that kale
packed in polyethylene-lined crates and protected by crushed ice keeps in excellent
condition for 3 weeks at 32ºF (0ºC) but only 1 week at 40ºF (4.4ºC) and 3 days at
50ºF (10ºC). Vitamin content and quality are retained better when wilting is
prevented.
PAC K AG I N G
Fresh-market beets are usually bunched by hand and are packaged in 35-pound halfcrates or 32-pound 4⁄5 bushel crates. Beets intended for processing are harvested as
needed into self-unloading trucks, bulk truck bodies, or trailers for immediate transport and processing. Chard is boxed in 32 pound crates that have holes in them to
keep the chard fresh.
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ANR Publication 8096
F O R M O R E I N F O R M AT I O N
You’ll find more information on beet and chard in the following ANR sources:
California Master Gardener Handbook. Publication 3382, 2002.
Postharvest Technology of Horticultural Crops, Third Edition, Publication 3311, 2002.
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Publication 8096
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